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Articles 1 - 30 of 100
Full-Text Articles in Physical Sciences and Mathematics
Chromium Speciation In Water Using Magnetic Polyaniline Nanoparticles Coupled With Microsampling Injection-Flame Atomic Absorption Spectroscopy, Osman Çaylak
Turkish Journal of Chemistry
The chromium speciation procedure was optimized using magnetic polyaniline nanoparticles (Fe3O4@PANI NPs) solid-phase extraction coupled with microsampling injection-flame atomic absorption spectrometry (MIS-FAAS). Chromium speciation was successfully achieved by Fe3O4@PANI NPs at pH 8.0. The recoveries obtained for Cr(III) and Cr(VI) were above 95% and under 5%, respectively. Recoveries of over 95% for Cr(III) from 40.0 mL of the sample were obtained using 25 mg Fe3O4@PANI NPs and 500 µL of 0.2% (w/v) thiourea (TU) solution prepared in 2 mol L–1 HCl as eluent. Total chromium as Cr(III) was extracted quantitatively after reducing the Cr(VI) to Cr(III). The linear range, detection …
Environmental Impact Assessment (Eia) Of As, Se, Sn, And Hg In Water And Sediments From The Egyptian Red Sea Ports, Lamiaa I. Mohamedein, Khalid M. El-Moselhy, Mohamed A. El-Sawy
Environmental Impact Assessment (Eia) Of As, Se, Sn, And Hg In Water And Sediments From The Egyptian Red Sea Ports, Lamiaa I. Mohamedein, Khalid M. El-Moselhy, Mohamed A. El-Sawy
Blue Economy
Background: Pollution monitoring is an important tool to protect the marine ecosystems where ports had been seen as a source of contamination affecting the public wellbeing. Methods: Therefore, in the present study, surface seawater and surficial sediment samples were collected from 19 stations covering six ports of the Egyptian Red Sea during summer 2017 and winter 2018. The concentrations of As, Se, Sn, and Hg were determined using the Hydride system MH10 coupled with atomic absorption spectrophotometer. Results: The obtained data revealed that mean values of AS, Se, Sn and Hg for water samples were ranged between …
Sugar Water Density Activity, Admin Stem For Success
Sugar Water Density Activity, Admin Stem For Success
STEM for Success Showcase
In this activity students learn about density using sugar water. Attached is the activity's lesson plan and a teacher reflection on the activity.
Mapping Per- And Polyfluoroalkyl Substances (Pfas) In South Carolina Surface Waters: Are There Hotspots?, Thomas C. Geiger
Mapping Per- And Polyfluoroalkyl Substances (Pfas) In South Carolina Surface Waters: Are There Hotspots?, Thomas C. Geiger
Senior Theses
Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in consumer products for their unique chemical properties. PFAS compounds are resistant to water, oil, heat, and grease, making them useful for a wide variety of everyday items such as non-stick cooking pans, food packaging, electronics, carpets, upholstery, paints, adhesives, and personal care products.1 The resilient nature of PFAS has made these compounds immensely popular with consumers but has since been considered a potential environmental and public health hazard for their ability to bioaccumulate and for their stability in the environment. More than 6000 PFAS have been discovered in the …
Ultrasound-Assisted Air-Jet Spinning Of Silk Fibroin-Soy Protein Nanofiber Composite Biomaterials., Futian Yang, Fang Wang, Janine Mazahreh, Xiao Hu
Ultrasound-Assisted Air-Jet Spinning Of Silk Fibroin-Soy Protein Nanofiber Composite Biomaterials., Futian Yang, Fang Wang, Janine Mazahreh, Xiao Hu
Faculty Scholarship for the College of Science & Mathematics
Ultrasound utilizes a non-radiation technology that can meet modern standards to gain access to cheap, reliable and sustainable modern energy. Ultrasound technology can be implemented in the field of biomaterials for its exceptional potential in controlling the shape of nanomaterials. This study presents the first example of the production of soy and silk fibroin protein composite nanofibers in various ratios via combining ultrasonic technology with air-spray spinning. Characterization of ultrasonic spun nanofibers was performed by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, water contact angle, water retention, enzymatic …
Determination Of Nitrate In Aqueous Media, Ebony Arauz Tellez, John Bohannon, Rebecca Mills, Virginia Tam, Isabelle Villarreal, Melissa C. Rhoten
Determination Of Nitrate In Aqueous Media, Ebony Arauz Tellez, John Bohannon, Rebecca Mills, Virginia Tam, Isabelle Villarreal, Melissa C. Rhoten
Spring Showcase for Research and Creative Inquiry
Determining the amount of inorganic ions in aqueous media is important in the food industry and environmentally. In the environment high levels of ions like nitrate (NO3-), nitrite (NO2-), and phosphate (PO43-) can lead to unhealthy conditions for aquatic species. Similarly, high levels of nitrate and nitrite can cause health issues in humans. One method for determining nitrate levels in aqueous samples involves reducing the nitrate species to nitrite via a redox reaction with finely divided zinc powder followed by conversion to a diazonium salt and complexation with 1-napthylamine to form a …
Grotthuss Molecular Dynamics Simulations For Modeling Proton Hopping In Electrosprayed Water Droplets., Lars Konermann, Scott Kim
Grotthuss Molecular Dynamics Simulations For Modeling Proton Hopping In Electrosprayed Water Droplets., Lars Konermann, Scott Kim
Chemistry Publications
Excess protons in water exhibit unique transport properties because they can rapidly hop along H-bonded water wires. Considerable progress has been made in unraveling this Grotthuss diffusion mechanism using quantum mechanical-based computational techniques. Unfortunately, high computational cost tends to restrict those techniques to small systems and short times. Molecular dynamics (MD) simulations can be applied to much larger systems and longer time windows. However, standard MD methods do not permit the dissociation/formation of covalent bonds, such that Grotthuss diffusion cannot be captured. Here, we bridge this gap by combining atomistic MD simulations (using Gromacs and TIP4P/2005 water) with proton hopping. …
Water-Based Lead Generation, Brian Olson
Water-Based Lead Generation, Brian Olson
Dissertations, Theses, and Capstone Projects
Water-based Lead Generation. The opioid epidemic and the SARS-CoV-2 pandemic are current serious challenges whose devastating effects could be assuaged through the development of new drugs. Opioids that are functional painkillers, that are less likely to cause overdose, and small molecule drugs that could inhibit the life cycle of SARS-CoV-2 would be useful. The work herein investigated the use of water molecules for lead generation in drug development against opioid receptors and SARS-CoV-2 viral proteins. In opioid receptor binding sites, purported bridging waters were obtained from crystal waters or from molecular dynamics simulations, as Hydration Site Analysis was used to …
Schiff Base Functionalized Silica Gel For Simultaneous Separation And Preconcentration Of Cu(Ii), Ni(Ii), And Cd(Ii) In Pharmaceuticals And Water Samples, Feyzullah Tokay, Sema Bağdat
Schiff Base Functionalized Silica Gel For Simultaneous Separation And Preconcentration Of Cu(Ii), Ni(Ii), And Cd(Ii) In Pharmaceuticals And Water Samples, Feyzullah Tokay, Sema Bağdat
Turkish Journal of Chemistry
A method for separation and preconcentration of Cu(II), Ni(II), and Cd(II) using N-N'-bis(5-methoxsalicylidene)-2-hydroxy-1,3-propanediamine modified silica gel was improved for aqueous samples and pharmaceuticals. Determination of the analytes was achieved by inductively coupled plasma optic emission spectrometry. The experimental conditions including pH value, sample volume, eluent type and volume, sorbent mass, sample, and eluent flow rates were optimized with univariate and multivariate optimization tools. The relative standard deviations of the method were 2.9% for Cu(II), 3.0% for Ni(II), and 3.3% for Cd(II) with recovery values between 98.8 ± 3.2-101.5 ± 3.0%. The limits of detection were found to be 62.4, 39.5, …
Scale-Up Of Flow-Electrode Capacitive Deionization Method For Hard Water Softening, Noah Henry
Scale-Up Of Flow-Electrode Capacitive Deionization Method For Hard Water Softening, Noah Henry
Williams Honors College, Honors Research Projects
This study’s purpose is to further document a capacitive deionization design that could be capable of purifying H2O at a household scale where clean water is otherwise unobtainable in applicable regions of the world. The hypothesis behind this study was continuously larger scaled electrochemical cell-units would increase their water softening capabilities in sustainable fashion. The trend at which performance will scale is currently unknown. The units studied were constructed using graphite plates, anion exchange membranes, cation exchange membranes, and Teflon channels. Three streams, two being CaCl2 solutions in DI H2O (one being concentrated with CaCl …
Supramolecular Solvent-Based Microextraction For The Preconcentration Of Pb2+ Andcd2+ Prior To Spectrophotometric Detection, Huma Zafar, Faheem Shah, Rafaqat Ali Khan, Asad Muhammad Khan, Jan Nisar, Bushra Ismail
Supramolecular Solvent-Based Microextraction For The Preconcentration Of Pb2+ Andcd2+ Prior To Spectrophotometric Detection, Huma Zafar, Faheem Shah, Rafaqat Ali Khan, Asad Muhammad Khan, Jan Nisar, Bushra Ismail
Turkish Journal of Chemistry
Supramolecular solvent-based dispersive liquid-liquid microextraction technique has been developed as a preconcentration tool for the determination of trace level of Pb2+ and Cd2+. Dodecanol dispersed in tetrahydrofuran has been utilized as a supramolecular-solvent system for the extraction of analytes prior to their quantitative determination with graphite furnace atomic absorption spectrophotometer. Both Pb2+ and Cd2+, which were efficiently extracted by supramolecular solvent system, were complexed with dithizone followed by the addition of supramolecular solvent. The experimental variables that could possibly influence the extraction efficiency, i.e. pH value, temperature, sample volume, centrifugation time, rate of centrifugation, ionic strength, etc. were subjected to …
A Theoretical Study Of Synchronous Proton Transfer In (Hf)N, (H2O) N, And (Hcl) N Where N = 3, 4, 5, Johnny Yang
A Theoretical Study Of Synchronous Proton Transfer In (Hf)N, (H2O) N, And (Hcl) N Where N = 3, 4, 5, Johnny Yang
Honors Theses
For (HF)n, (H2O)n, and (HCl)n (n = 3 − 5), we have rigorously characterized the structures for the minima and transition states for synchronous proton transfer (SPT) with the CCSD(T) method and aug-cc-pVTZ basis set. The electronic barrier heights (∆E†) associated with these transition states have also been computed with the explicitly correlated CCSD(T)-F12 method and the aug-cc-pVQZ-F12 basis set (abbreviated aQZ-F12). (HCl)n (n = 3 − 5) SPT transition states have not been previously identified to the best of our knowledge, and they have been found …
Can CP Be Less Than CV?, Yingbin Ge, Samuel L. Montgomery, Gabriel L. Borrello
Can CP Be Less Than CV?, Yingbin Ge, Samuel L. Montgomery, Gabriel L. Borrello
All Faculty Scholarship for the College of the Sciences
Can CP be less than CV? This is a fundamental question in physics, chemistry, chemical engineering, and mechanical engineering. This question hangs in the minds of many students, instructors, and researchers. The first instinct is to answer “Yes, for water between 0 and 4 °C” if one knows that water expands as temperature decreases in this temperature range. The same question is asked in several Physical Chemistry and Physics textbooks. Students are supposed to answer that water contracts when heated at below 4 °C in an isobaric process. Because work is done to the contracting water, less …
Fate Of Persistent Contaminants And Emerging Algal Toxins In Drinking Water And The Environment, Danielle Christine Westerman
Fate Of Persistent Contaminants And Emerging Algal Toxins In Drinking Water And The Environment, Danielle Christine Westerman
Theses and Dissertations
Population growth and global climate change has resulted in the degradation of pristine water sources, causing issues like saltwater intrusion, persistent harmful algal blooms, and drought from population growth. Future reliance on alternative sources of drinking water to is expected globally, therefore, nontraditional sources of drinking water are becoming increasingly vital sources of potable water around the world. For example, desalination (typically by reverse osmosis), despite its high energy demands and high cost, is being utilized all over the world to meet drinking water demand. Wastewater reuse, the additional treatment of wastewater to produce drinking water, either directly or indirectly, …
Aggregation And Degradation Of Dispersants And Oil By Microbial Exopolymers (Addomex): Toward A Synthesis Of Processes And Pathways Of Marine Oil Snow Formation In Determining The Fate Of Hydrocarbons, Antonietta Quigg, Peter H. Santschi, Chen Xu, Kai Ziervogel, Manoj Kamalanathan, Wei-Chun Chin, Adrian B. Burd, Andrew Wozniak, Patrick G. Hatcher
Aggregation And Degradation Of Dispersants And Oil By Microbial Exopolymers (Addomex): Toward A Synthesis Of Processes And Pathways Of Marine Oil Snow Formation In Determining The Fate Of Hydrocarbons, Antonietta Quigg, Peter H. Santschi, Chen Xu, Kai Ziervogel, Manoj Kamalanathan, Wei-Chun Chin, Adrian B. Burd, Andrew Wozniak, Patrick G. Hatcher
Chemistry & Biochemistry Faculty Publications
Microbes (bacteria, phytoplankton) in the ocean are responsible for the copious production of exopolymeric substances (EPS) that include transparent exopolymeric particles. These materials act as a matrix to form marine snow. After the Deepwater Horizon oil spill, marine oil snow (MOS) formed in massive quantities and influenced the fate and transport of oil in the ocean. The processes and pathways of MOS formation require further elucidation to be better understood, in particular we need to better understand how dispersants affect aggregation and degradation of oil. Toward that end, recent work has characterized EPS as a function of microbial community and …
Mxenes As Flow Electrodes For Capacitive Deionization Of Wastewater, Naqsh E. Mansoor
Mxenes As Flow Electrodes For Capacitive Deionization Of Wastewater, Naqsh E. Mansoor
Boise State University Theses and Dissertations
The energy-water nexus poses an integrated research challenge, while opening up an opportunity space for the development of energy efficient technologies for water remediation. Capacitive Deionization (CDI) is an upcoming reclamation technology that uses a small applied voltage applied across electrodes to electrophoretically remove dissolved ionic impurities from wastewater streams. Similar to a supercapacitor, the ions are stored in the electric double layer of the electrodes. Reversing the polarity of applied voltage enables recovery of the removed ionic impurities, allowing for recycling and reuse. Simultaneous materials recovery and water reclamation makes CDI energy efficient and resource conservative, with potential to …
Protonic Capacitor: Elucidating The Biological Significance Of Mitochondrial Cristae Formation, James Weifu Lee
Protonic Capacitor: Elucidating The Biological Significance Of Mitochondrial Cristae Formation, James Weifu Lee
Chemistry & Biochemistry Faculty Publications
For decades, it was not entirely clear why mitochondria develop cristae? The work employing the transmembrane-electrostatic proton localization theory reported here has now provided a clear answer to this fundamental question. Surprisingly, the transmembrane-electrostatically localized proton concentration at a curved mitochondrial crista tip can be significantly higher than that at the relatively flat membrane plane regions where the proton-pumping respiratory supercomplexes are situated. The biological significance for mitochondrial cristae has now, for the first time, been elucidated at a protonic bioenergetics level: 1) The formation of cristae creates more mitochondrial inner membrane surface area and thus more protonic capacitance for …
Modeling The Alkaline Hydrolysis Of Diaryl Sulfate Diesters: A Mechanistic Study, Klaudia Szeler, Nicholas H. Williams, Alvan C. Hengge, Shina C. Kamerlin
Modeling The Alkaline Hydrolysis Of Diaryl Sulfate Diesters: A Mechanistic Study, Klaudia Szeler, Nicholas H. Williams, Alvan C. Hengge, Shina C. Kamerlin
Chemistry and Biochemistry Faculty Publications
Phosphate and sulfate esters have important roles in regulating cellular processes. However, while there has been substantial experimental and computational investigation of the mechanisms and the transition states involved in phosphate ester hydrolysis, there is far less work on sulfate ester hydrolysis. Here, we report a detailed computational study of the alkaline hydrolysis of diaryl sulfate diesters, using different DFT functionals as well as mixed implicit/explicit solvation with varying numbers of explicit water molecules. We consider the impact of the computational model on computed linear free-energy relationships (LFER) and the nature of the transition states (TS) involved. We obtain good …
Filtration Apparatus Design For Oil-Water Separation Using Membranes And Sponges, Alec Jerger
Filtration Apparatus Design For Oil-Water Separation Using Membranes And Sponges, Alec Jerger
Williams Honors College, Honors Research Projects
It can be difficult to separate water and oil emulsions through traditional filtration. Therefore, investigations of filtering using thermo-responsive (TR) polymers, in this case poly(vinyl methyl ether) (PVME), was conducted. It’s hypothesized that below its lower critical solution temperature (LCST), PVME has an affinity for water while oil substances do not. Above the LCST the opposite will be true. To verify this hypothesis, iterations of filtration designs were created to provide optimum control over the parameters to measure flow. The final optimized experimental apparatus was a Chromaflex glass column which was air tight and controlled all parameters besides fluid flow. …
Kentucky's Environmental Future, Fall/Winter 2004, Issue 9
Kentucky's Environmental Future, Fall/Winter 2004, Issue 9
Sustain Magazine
No abstract provided.
Molecular Rotation In 3 Dimensions At An Air/Water Interface Using Femtosecond Time Resolved Sum Frequency Generation, Yi Rao, Yuqin Qian, Gang-Hua Deng, Ashlie Kinross, Nicholas J. Turro, Kenneth B. Eisenthal
Molecular Rotation In 3 Dimensions At An Air/Water Interface Using Femtosecond Time Resolved Sum Frequency Generation, Yi Rao, Yuqin Qian, Gang-Hua Deng, Ashlie Kinross, Nicholas J. Turro, Kenneth B. Eisenthal
Chemistry and Biochemistry Faculty Publications
This paper presents the first study of the rotations of rigid molecules in 3 dimensions at the air/water interface, using the femtosecond time resolved sum frequency generation (SFG) technique. For the purpose of this research, the aromatic dye molecule C153 was chosen as an example of a molecule having two functional groups that are SFG active, one being the hydrophilic −−C==O group and the other the hydrophobic −−CF3 group. From polarized SFG measurements, the orientations of the two chromophores with respect to the surface normal were obtained. On combining these results with the known relative orientation of the two …
Spatial Patterns Of Particulate Organic Carbon Concentrations And Isotopic Signatures Across A Salinity Gradient In A River Dominated Estuary, Lauren E. Alvaro, John C. Lehrter, Mai Fung
Spatial Patterns Of Particulate Organic Carbon Concentrations And Isotopic Signatures Across A Salinity Gradient In A River Dominated Estuary, Lauren E. Alvaro, John C. Lehrter, Mai Fung
Gulf and Caribbean Research
No abstract provided.
Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez
Assessment Of Quantity And Quality Of Microplastics In The Sediments, Waters, Oysters, And Selected Fish Species In Key Sites Along The Bombong Estuary And The Coastal Waters Of Ticalan In San Juan, Batangas, Emilyn Q. Espiritu, Sophia Angeli Sn Dayrit, Annabel Soledad O. Coronel, Natasha Sophia C. Paz, Pilar Isabel L. Ronquillo, Virgil Christian G. Castillo, Erwin P. Enriquez
Chemistry Faculty Publications
Microplastics (or MPs; < 5 mm in size) pollution is largely unstudied in the Philippines. From an environmental sustainability standpoint, it is important to understand the characteristics, abundance, and environmental fate of plastic debris of various sizes, and these include microplastics that are not more easily and readily detected. In this study, we assessed the extent of microplastics contamination in the sediments, waters, oysters, and selected fishes found in the rivers and coastal areas of Ticalan, Batangas, which were identified from water quality parameters as Class C and CS, respectively. The microplastics were extracted from these samples by chemical digestion of the matrix, series of filtration, and separation by flotation through a density gradient to finally isolate the microplastics which were not dissolved by chemical digestion. The isolated samples were imaged by optical microscopy and characterized based on their descriptive attributes. The results showed the presence of microplastics in all the samples tested, which were found mostly in the form of filaments, fragments, films, and pellets – with most showing weathered, degraded, or angular and irregular surfaces. Identification was done through spectral matching of the Fourier transform infrared spectra of isolated fragments with that of known plastics, although identification in some cases is made uncertain by possibility of degradation of the plastics in the environment. The majority of the isolates showed signature absorption bands of the C-H stretching vibrations of polyethylene-based plastics.
Enhanced Acidity Of Acetic And Pyruvic Acids On The Surface Of Water, Alexis J. Eugene, Elizabeth A. Pillar, Agustín J. Colussi, Marcelo I. Guzman
Enhanced Acidity Of Acetic And Pyruvic Acids On The Surface Of Water, Alexis J. Eugene, Elizabeth A. Pillar, Agustín J. Colussi, Marcelo I. Guzman
Chemistry Faculty Publications
Understanding the acid–base behavior of carboxylic acids on aqueous interfaces is a fundamental issue in nature. Surface processes involving carboxylic acids such as acetic and pyruvic acids play roles in (1) the transport of nutrients through cell membranes, (2) the cycling of metabolites relevant to the origin of life, and (3) the photooxidative processing of biogenic and anthropogenic emissions in aerosols and atmospheric waters. Here, we report that 50% of gaseous acetic acid and pyruvic acid molecules transfer a proton to the surface of water at pH 2.8 and 1.8 units lower than their respective acidity constants pKa …
Crown Ether Effects On The Location Of Charge Carriers In Electrospray Droplets: Implications For The Mechanism Of Protein Charging And Supercharging., Haidy Metwally, Lars Konermann
Crown Ether Effects On The Location Of Charge Carriers In Electrospray Droplets: Implications For The Mechanism Of Protein Charging And Supercharging., Haidy Metwally, Lars Konermann
Chemistry Publications
"Native" electrospray ionization (ESI) mass spectrometry (MS) aims to transfer proteins from solution into the gas phase while maintaining solution-like structures and interactions. The ability to control the charge states of protein ions produced in these experiments is of considerable importance. Supercharging agents (SCAs) such as sulfolane greatly elevate charge states without significantly affecting the protein structure in bulk aqueous solution. The origin of native ESI supercharging remains contentious. According to one model, SCAs trigger unfolding within ESI droplets. In contrast, the "charge trapping model" envisions that SCAs impede the ejection of charge carriers (e.g., NH4+ or Na …
Water Dynamics And The Effect Of Static And Alternating Electric Fields, Mohammadmahdi Shafiei Alavijeh
Water Dynamics And The Effect Of Static And Alternating Electric Fields, Mohammadmahdi Shafiei Alavijeh
Theses and Dissertations
Having a net dipole moment, water molecules tend to align with an external electric field. The re-orientation of water molecules to align with the field direction can result in structural and dynamic changes in liquid water. Studying these changes can help us to understand the role of an E-field in many biological systems, chemical reactions, and many technological advancements.
In short, the application of static electric fields causes molecules to stay aligned with the field, so, fewer hydrogen bonds break, and molecules have slower dynamics. This type of field can be used when the mobility of water molecules needs to …
Expeditious Green Synthesis Of Versatile Organic Compounds By Diverse Methods, Bimal K. Banik
Expeditious Green Synthesis Of Versatile Organic Compounds By Diverse Methods, Bimal K. Banik
Chemistry Faculty Publications and Presentations
Synthesis of organic compounds requires organic solvents and reagents to promote them. Very often, toxic solvents are used for this purpose. Many organic reactions require molar proportion of reactants and reagents to accomplish the goal. Some reactions require longer reaction times and produce products without control of stereochemistry. Therefore, development of facile and effective organic reactions under environmentally friendly conditions is necessary. In this perspective, several reactions are discussed that are performed by microwave-induced reactions, catalytic procedures, in the absence of any solvents, one-pot method and in water. Important reactions are chosen to investigate the feasibility of conducting these reactions …
Analysis Of The Red And Green Optical Absorption Spectrum Of Gas Phase Ammonia, Nikolai F. Zobov, Phillip A. Coles, Roman I. Ovsyannikov, Aleksandra A. Kyuberis, Robert J. Hargreaves, Peter F. Bernath, Jonathan Tennyson, Sergei N. Yurchenko, Oleg L. Polyansky
Analysis Of The Red And Green Optical Absorption Spectrum Of Gas Phase Ammonia, Nikolai F. Zobov, Phillip A. Coles, Roman I. Ovsyannikov, Aleksandra A. Kyuberis, Robert J. Hargreaves, Peter F. Bernath, Jonathan Tennyson, Sergei N. Yurchenko, Oleg L. Polyansky
Chemistry & Biochemistry Faculty Publications
Room temperature NH3 absorption spectra recorded at the Kitt Peak National Solar Observatory in 1980 are analyzed. The spectra cover two regions in the visible: 15,200 - 15,700 cm-1 and 17,950 - 18,250 cm-1. These high overtone rotation-vibration spectra are analyzed using both combination differences and variational line lists. Two variational line lists were computed using the TROVE nuclear motion program: one is based on an ab initio potential energy surface (PES) while the other used a semi-empirical PES. Ab initio dipole moment surfaces are used in both cases. 95 energy levels with J = 1 …
The Development Of A Simplified Alkalinity Titration Analyzer, Reba Van Beusekom
The Development Of A Simplified Alkalinity Titration Analyzer, Reba Van Beusekom
Graduate Student Theses, Dissertations, & Professional Papers
Alkalinity is the acid neutralizing capacity for water, meaning alkalinity measures how sensitive an aquatic system is to acidic inputs. Currently, there are various measuring systems for alkalinity available including chemical test kits, potentiometric techniques, and colorimetric methods. Commercially available products lack the ease of use combined with precision and accuracy desired for on-line process and environmental monitoring. The goal of this project is to develop a simplified alkalinity titration analyzer, called the easyTMT, to measure alkalinity with precision and accuracy comparable to the best conventional methods. The system, under development, uses the Tracer Monitored Titration (TMT) technique. TMT …
Characterization Of Γ-Butyrolactone Rings: A Computational And Toxicological Study, Donald C. Kidd
Characterization Of Γ-Butyrolactone Rings: A Computational And Toxicological Study, Donald C. Kidd
Masters Theses
Given the declining state of the natural environment, identifying green methodologies in synthetic chemistry is becoming paramount. An under explored area of green chemistry, is the use of catalytic systems in green solvents. One interesting concept in green chemistry is the use of N-Heterocyclic Carbenes (NHCs) as organocatalysts.
Thiamine or vitamin B1 was one of the first NHCs recognized. Thiamine is required for carbohydrate metabolism and helps the cell produce adenosine triphosphate (ATP). Over the last 20 years NHCs have been found to be efficient catalysts in carbon-carbon bond forming reactions.
But to date, little research has been done exploring …